19668
domain: N
Appears in sequences
- a(n) = T(2n-1,n), where T is the array defined in A025177.at n=6A025183
- Numbers k such that sopf(k) = sopf(k+3), where sopf(k) = A008472(k).at n=23A063969
- Numbers n such that phi(reverse(n)) = sigma(n).at n=9A070835
- Row sums of A163334 and A163336.at n=28A163342
- Mirror of the triangle A193961.at n=45A193962
- a(n) = 9*3^n - 15.at n=6A277104
- Integers k equal to the sum over A000203(t) mod t, for some steps, starting with t = k and then using the result to feed the next calculation.at n=35A377001
- a(1) = 2; for n > 1, a(n) = a(n-1)*prime(n) if a(n-1) <= prime(n), otherwise a(n) = a(n-1) mod prime(n).at n=34A387775